HOT-START
A GYTR hot-start finds its way under the
bars, which are equipped with Sunline
levers. These items replace the standard
levers that are prone to snapping in a
decent crash. The change means any
movement in the Sunline levers doesn’t
affect the hot-start lever’s performance.

If racing improves the breed, then Serco’s ten-year tenure with the
Yamaha YZ250F means that success is never very far away.
martin child

t’s been a decade of association
between Serco and Yamaha at
national motocross level and the most
noticeable fruit of that merger was the
pair of Australian Pro Lites MX titles,
won by Cameron Taylor in 2005
and then by Jake Moss in 2007.
Serco’s entry into motorsport
started way back in the day at the
Thumper Nats series, with riders like
Mark Avard and Mick Cotter. The
decision was then to go for an all-out
assault on the Aussie MX Nationals.
After building a team, Serco went
direct to Yamaha Australia to see
what deal could be done there. They
came away with the company’s 100%
backing, and the task of running
the official factory Lites team.
Through the years, there’s
been some well-known butts
on the Serco saddles – riders
such as Daniel McCoy, Robbie
Marshall, Adam Cini, Mitch
Hoad, Brenden Harrison and
Cameron Taylor. The current
line-up includes Jake Moss,
Ford Dale and Kirk Gibbs.
Kirk’s Serco Yoshimura
Yamaha YZ250F is a direct
descendant from the bike the
team used in their first season in
2001. The then brand-new model
ran a steel frame, before being
replaced by a lighter, stiffer alloy
frame when the production model
got a thorough revamp in 2006.
Although not heavily modified,
Kirk’s bike is the result of a stable
team working on a known platform.
After all, the guys at Serco have been
travelling the width and breadth of
Australia for the past ten years, getting
the best out of the YZ250F.

48

CLUTCH
The biggest change to the engine is the
clutch operation – Serco runs a wet-sump
kit. This allows the clutch plates to bathe
in the black stuff and ‘see’ more oil than
standard, meaning cooler running and less
wear. The clutch itself is a Hinson unit,
from basket to springs to plates.

ENGINE
Kirk’s engine has been built with extra
power in mind. It runs a CP piston and a
modified head, along with special Hotcams.
The gearbox and ratios remain standard,
as do the cooling lines. The radiators
remain stock, although a CB4 radiator
cap is used to deal with higher pressures.

CARBURETTOR
The Serco YZ250F runs a Dynojet carb
kit to sync the engine’s performance to
the Yoshimura full titanium exhaust system
that’s fitted. The carby also gets treated
to a R&D fuel bowl and DNA filter, which
helps it breathe easier than standard. The
stock throttle tube is swapped for a fasteracting, more durable Pro Taper alloy item.

49

SERCO’S

BIKE
DISSECTED

SCREAMER

HOT-START
A GYTR hot-start finds its way under the
bars, which are equipped with Sunline
levers. These items replace the standard
levers that are prone to snapping in a
decent crash. The change means any
movement in the Sunline levers doesn’t
affect the hot-start lever’s performance.

If racing improves the breed, then Serco’s ten-year tenure with the
Yamaha YZ250F means that success is never very far away.
martin child

t’s been a decade of association
between Serco and Yamaha at
national motocross level and the most
noticeable fruit of that merger was the
pair of Australian Pro Lites MX titles,
won by Cameron Taylor in 2005
and then by Jake Moss in 2007.
Serco’s entry into motorsport
started way back in the day at the
Thumper Nats series, with riders like
Mark Avard and Mick Cotter. The
decision was then to go for an all-out
assault on the Aussie MX Nationals.
After building a team, Serco went
direct to Yamaha Australia to see
what deal could be done there. They
came away with the company’s 100%
backing, and the task of running
the official factory Lites team.
Through the years, there’s
been some well-known butts
on the Serco saddles – riders
such as Daniel McCoy, Robbie
Marshall, Adam Cini, Mitch
Hoad, Brenden Harrison and
Cameron Taylor. The current
line-up includes Jake Moss,
Ford Dale and Kirk Gibbs.
Kirk’s Serco Yoshimura
Yamaha YZ250F is a direct
descendant from the bike the
team used in their first season in
2001. The then brand-new model
ran a steel frame, before being
replaced by a lighter, stiffer alloy
frame when the production model
got a thorough revamp in 2006.
Although not heavily modified,
Kirk’s bike is the result of a stable
team working on a known platform.
After all, the guys at Serco have been
travelling the width and breadth of
Australia for the past ten years, getting
the best out of the YZ250F.

48

CLUTCH
The biggest change to the engine is the
clutch operation – Serco runs a wet-sump
kit. This allows the clutch plates to bathe
in the black stuff and ‘see’ more oil than
standard, meaning cooler running and less
wear. The clutch itself is a Hinson unit,
from basket to springs to plates.

ENGINE
Kirk’s engine has been built with extra
power in mind. It runs a CP piston and a
modified head, along with special Hotcams.
The gearbox and ratios remain standard,
as do the cooling lines. The radiators
remain stock, although a CB4 radiator
cap is used to deal with higher pressures.

CARBURETTOR
The Serco YZ250F runs a Dynojet carb
kit to sync the engine’s performance to
the Yoshimura full titanium exhaust system
that’s fitted. The carby also gets treated
to a R&D fuel bowl and DNA filter, which
helps it breathe easier than standard. The
stock throttle tube is swapped for a fasteracting, more durable Pro Taper alloy item.

49

BIKE
DISSECTED

COCKPIT
Pro Taper triple clamps
find their way onto the
steering head. The offset
remains standard, though
Kirk runs the clamps in
the frontal position for
more working room in the
cockpit. The Pro Taper
handlebars feature a Ricky
Carmichael bend and are
bolted to standard risers.

WHEELS

Grip
A Factory Effex pleated seat helps when
the conditions dictate more rider grip
when seated. When standing, Kirk can
rely on the copious amounts of gripper

tape that covers the sideplates. The
Serco Yami runs the stock super-wide
footpegs, which have been production
items since 2005.

THE WENCH:
MICHAEL MARTY

Michael has been with the Serco Yamaha
team from day one, back in 2001. He’s seen
a host of riders through the years and more
than a couple of championship trophies
in that time. He’s been working with the
quietly spoken 22-year-old Gibbs since he
joined the team in the beginning of 2009.
Is it easy to set the bike up for Kirk?
MM: Kirk’s no different to the other top
riders. He’s always looking for more. On
the 250F, you just need to get as much
horsepower as you can – the more, the

50

Although the hubs and
spokes remain standard,
the Serco YZ250F runs
Excel rims and Pirelli tyres,
with Kirk preferring the
mid-hard compound at most
tracks. The front brake runs
an oversized GYTR disc
though the rear remains
bog-stock. The standard
pads are retained, too.

better. None of the top guys ever say they
need less. Before the season started, we got
Kirk to moto loads and then spent days and
days on the dyno. We then gave it back to
him at the track. There’s always a bit more
you can find through different cams.
Does Yamaha help with set-up?
As we’ve been running the official Yamaha
team for so long now, we have the biggest
database on settings so we tend not to have
to ask them these days.
How does Kirk like his suspension?
With Kirk, he’s been here for three years
now so we pretty much know what he
wants. This year we started off with
settings from last year and worked from
there. We’ve definitely found better

settings this year. It’s not a massive
change, but it is different and he’s going
with it. The bike runs a very firm fork, so
it’ll never bottom-out. And the rear’s not
as hard as the front.
Is the engine tuned for aggression
or traction off the bottom?
Yes, we try to get it aggressive off the
bottom so when he comes out of a corner,
the power’s there and he’s got a good hit.
It’s not so critical on a 450cc, but on a
250cc you always want the power there.
Is there anything he finds critical?
He will only run a 90-section front tyre – if
I try to sneak an 80-profile tyre on, he’ll
pick it on the track every time. He hates
the lower profile tyre.